Among conventionally known methods for manufacturing a medium such as an optical disc on which information is recorded in an optically retrievable manner is a manufacturing method as disclosed in Japanese Laid-Open Patent Application, Publication (JP-A) No. 3-40244. In this technique, first, a glass substrate made of glass that is inorganic matter is coated with a solution made of metal alcoholate, water, hydrochloric acid, alcohol, and other components, to form a predetermined layer. Then, while a mold made of plastic is being applied to this layer, a primary burning operation is carried out at 60-120 degrees centigrade.
Thereafter, the glass substrate is separated from the mold, and subjected to a secondary burning operation at 250-400 degrees centigrade to remove organic components such as a solvent, an additive, etc., so that an amorphous metal oxide layer having a desired pattern of pits and projections (pit pattern) is formed on the glass substrate. By following the process described above, information is recorded as a fine pattern of pits and projections in the metal oxide layer on the glass substrate.